bpf: add PC to fault reporting using dt_probe_error()

Signed-off-by: Kris Van Hees <kris.van.hees@oracle.com> Reviewed-by: Eugene Loh <eugene.loh@oracle.com>
oracle · May 25, 2023 · bfaf540 · bfaf540
1 parent 083a2fe
commit bfaf540
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Showing 5 changed files with 8 additions and 6 deletions.
diff --git a/bpf/get_bvar.c b/bpf/get_bvar.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
 /*
- * Copyright (c) 2020, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2020, 2023, Oracle and/or its affiliates. All rights reserved.
  */
 #include <linux/bpf.h>
 #include <stddef.h>
@@ -23,13 +23,14 @@ extern struct bpf_map_def cpuinfo;
 extern struct bpf_map_def probes;
 extern struct bpf_map_def state;
 
+extern uint64_t PC;
 extern uint64_t STBSZ;
 extern uint64_t STKSIZ;
 extern uint64_t BOOTTM;
 
 #define error(dctx, fault, illval) \
 	({ \
-		dt_probe_error((dctx), -1, (fault), (illval)); \
+		dt_probe_error((dctx), (uint64_t)&PC, (fault), (illval)); \
 		-1; \
 	})
 

diff --git a/bpf/speculation.c b/bpf/speculation.c
@@ -20,6 +20,7 @@
 
 extern struct bpf_map_def specs;
 extern struct bpf_map_def state;
+extern uint64_t PC;
 extern uint64_t NSPEC;
 
 /*
@@ -151,7 +152,7 @@ dt_speculation_set_drainable(const dt_dctx_t *dctx, uint32_t id)
 	if ((spec = bpf_map_lookup_elem(&specs, &id)) == NULL) {
 		if (id <= (uint64_t) &NSPEC)
 			return 0;
-		dt_probe_error(dctx, -1, DTRACEFLT_ILLOP, 0);
+		dt_probe_error(dctx, (uint64_t)&PC, DTRACEFLT_ILLOP, 0);
 		return -1;
 	}
 	spec->draining = 1;

diff --git a/test/unittest/speculation/err.CommitWithInvalid.r b/test/unittest/speculation/err.CommitWithInvalid.r
@@ -1,3 +1,3 @@
 
 -- @@stderr --
-dtrace: error on enabled probe ID 4 (ID 1: dtrace:::BEGIN): illegal operation in action #2
+dtrace: error on enabled probe ID 4 (ID 1: dtrace:::BEGIN): illegal operation in action #2 at BPF pc NNN
diff --git a/test/unittest/speculation/err.DiscardWithInvalid.r b/test/unittest/speculation/err.DiscardWithInvalid.r
@@ -1,3 +1,3 @@
 
 -- @@stderr --
-dtrace: error on enabled probe ID 4 (ID 1: dtrace:::BEGIN): illegal operation in action #2
+dtrace: error on enabled probe ID 4 (ID 1: dtrace:::BEGIN): illegal operation in action #2 at BPF pc NNN
diff --git a/test/unittest/speculation/tst.negcommit.r b/test/unittest/speculation/tst.negcommit.r
@@ -3,4 +3,4 @@
 
 -- @@stderr --
 dtrace: script 'test/unittest/speculation/tst.negcommit.d' matched 2 probes
-dtrace: error on enabled probe ID 2 (ID 1: dtrace:::BEGIN): illegal operation in action #1
+dtrace: error on enabled probe ID 2 (ID 1: dtrace:::BEGIN): illegal operation in action #1 at BPF pc NNN